Partial versus complete thymus removal during infant heart surgery

Impact of Thymectomy on Immune Response in Infants 12 Months After Cardiac Surgery: a Single-centre Prospective Study

This will test whether removing only part of the thymus instead of the whole gland during heart surgery helps preserve immune function in infants under 6 months.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 70 (estimated)
• Ages: N/A to 6 Months
• Sex: All
• Sponsor: Nantes University Hospital (Academic / other)
• Locations: 2 sites (Nantes and 1 other locations)
• Trial ID: NCT07019857 on ClinicalTrials.gov

What this trial studies

This is a prospective, interventional, single-center study at Nantes University Hospital comparing immune outcomes after partial versus complete thymectomy in infants undergoing cardiac surgery before 6 months of age. Seventy infants are enrolled non-randomly into three groups: complete thymectomy during cardiopulmonary bypass, partial thymectomy during cardiopulmonary bypass, and a control group undergoing cardiac or non-cardiac surgery without thymectomy. Blood samples are collected at the time of surgery and at 12 months postoperatively to measure T-cell counts, maturation markers, and immunological function, and clinical infection rates are tracked. The study aims to see if partial thymectomy better preserves cellular immunity and reduces infection risk compared with total thymus removal.

Who should consider this trial

Good fit: Infants aged 0–6 months born at ≥37 weeks and scheduled for cardiac surgery with cardiopulmonary bypass at Nantes University Hospital, with parental consent, are the primary candidates (with separate control groups for cardiac surgery without thymectomy and non-cardiac surgery).

Not a fit: Children older than six months, preterm infants, or those whose anatomy prevents a partial thymectomy are unlikely to benefit from the findings of this trial.

Why it matters

Potential benefit: If partial thymectomy preserves T-cell development, it could lower infants' infection risk after heart surgery and improve long-term immune health.

How similar studies have performed: Previous observational studies have linked complete infant thymectomy to persistent T-cell changes and higher infection rates, but direct comparisons between partial and complete thymectomy are limited and relatively untested.

Eligibility criteria

Inclusion Criteria:

* \- Children aged between 0 and 6 months;
* Born at a gestational age \> 37 weeks' gestation;
* With an indication for cardiac surgery under CEC at Nantes University Hospital;
* Cardiopediatric follow-up planned at Nantes University Hospital;
* Written agreement signed by legal guardians to participate in the study.

For the control groups:

* Control group A (cardiac surgery without thymectomy):

  * Children aged between 0 and 6 months of age;
  * Born at a gestational age \> 37 SA;
  * Indicated for thoracotomy cardiac surgery at Nantes University Hospital;
  * Cardiopediatric follow-up planned at Nantes University Hospital;
  * Written agreement signed by legal guardians to participate in the study.
* Control group B (non-cardiac surgery)

  * Children aged between 0 and 6 months;
  * Born at a gestational age \> 37 SA;
  * Indicated for non-cardiac surgery (ENT or visceral surgery at Nantes University Hospital);
  * Planned follow-up surgery at Nantes University Hospital;
  * Written agreement signed by legal guardians to participate in the study.

Exclusion Criteria :

* Gestational age \< 37 SA;
* With a history of cardiac surgery under ECG;
* And/or with heart disease requiring further surgery within 12 months of the 1st surgery (e.g. pulmonary cerclage, systemic pulmonary anastomosis).
* And/or a history of partial or complete thymectomy;
* Receiving long-term immunosuppressive treatment;
* Post-operative follow-up planned in a hospital other than Nantes University Hospital, or moving house planned during the follow-up period;
* parental refusal.

Exclusion Criteria:

* \- Gestational age \< 37 SA;
* With a history of cardiac surgery under ECG;
* And/or with heart disease requiring further surgery within 12 months of the 1st surgery (e.g. pulmonary cerclage, systemic pulmonary anastomosis).
* And/or a history of partial or complete thymectomy;
* Receiving long-term immunosuppressive treatment;
* Post-operative follow-up planned in a hospital other than Nantes University Hospital, or moving house planned during the follow-up period;
* parental refusal.

Where this trial is running

Nantes and 1 other locations

• CHU de Nantes — Nantes, France (Not_yet_recruiting)
• Chu de Nantes — Nantes, France (Recruiting)

Study contacts

• Principal investigator: Alexis Chenouard, PH — Nantes University Hospital
• Study coordinator: Alexis Chenouard, PH

Conditions Congenital Heart Defects; Thymectomy; Immunological Deficiency Syndrome; Cardiac Surgery; Infant; Immunity; Lymphocytes; TRECs